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<html lang="zh">
<head>
    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    
<button class="btn">立即支付</button>

<script>
var btn = document.querySelector('.btn');
btn.onclick = function (){
    // 跳转到b页面
    open('./b.html','_self');
}


</script>
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